使用jq过滤掉元素的特定json个数组字段

Question

我运行一个 aws rds describe-instances 我得到了一个 json 实例数组，大致如下：

"DBInstances": [
        {
            "DBInstanceIdentifier": "my-rds",
            "Endpoint": {
                "HostedZoneId": "XXXXXXXXXXXX"
            },
            "DBSecurityGroups": [],
            "VpcSecurityGroups": [
                {
                    "VpcSecurityGroupId": "sg-12345",
                    "Status": "active"
                },
                {
                    "VpcSecurityGroupId": "sg-12345",
                    "Status": "active"
                }
            ],
            "DBParameterGroups": [
                {
                    "DBParameterGroupName": "postgres-12",
                    "ParameterApplyStatus": "in-sync"
                }
            ],
            "AvailabilityZone": "us-west-1c",
            "DBSubnetGroup": {
                "VpcId": "vpc-123456",
                "SubnetGroupStatus": "Complete",
                "Subnets": [
                    {
                        "SubnetIdentifier": "subnet-123456",
                        "SubnetAvailabilityZone": {
                            "Name": "us-west-1b"
                        },
                        "SubnetOutpost": {},
                        "SubnetStatus": "Active"
                    },
                    {
                        "SubnetIdentifier": "subnet-12345",
                        "SubnetAvailabilityZone": {
                            "Name": "us-west-1c"
                        },
                        "SubnetOutpost": {},
                        "SubnetStatus": "Active"
                    },
                    {
                        "SubnetIdentifier": "subnet-12345",
                        "SubnetAvailabilityZone": {
                            "Name": "us-west-1e"
                        },
                        "SubnetOutpost": {},
                        "SubnetStatus": "Active"
                    }
                ]
            },
            "EngineVersion": "11.9",
            "AutoMinorVersionUpgrade": true,
            "ReadReplicaDBInstanceIdentifiers": [],
            "LicenseModel": "foobar",
            "OptionGroupMemberships": [
                {
                    "OptionGroupName": "randomname",
                    "Status": "in-sync"
                }
            ],
        },
    }

输出t运行很明显。

有没有办法使用（jq可能？）来打印：

a) DBInstances 数组的所有元素

并且只为每个元素打印

b) DBInstanceIdentifier 和 EngineVersion?

Answer 1

已解决，不是 .jq，而是 aws cli 功能：

aws rds describe-db-instances --query 'DBInstances[*].[DBInstanceIdentifier, EngineVersion]'

Answer 2

您可以使用以下 JQ 过滤器：

.DBInstances[] | [ .DBInstanceIdentifier, .EngineVersion ]

在哪里

.DBInstances[] 遍历 DBInstances 数组
[ .DBInstanceIdentifier, .EngineVersion ] 创建一个仅包含 DBInstanceIdentifier 和 EngineVersion 键的数组

jq '.DBInstances[] | [ .DBInstanceIdentifier, .EngineVersion ]'

JqPlay Demo

根据您当前的 JSON 示例（DBInstances 数组中只有 1 个项目），结果是：

[
  "my-rds",
  "11.9"
]

使用jq过滤掉元素的特定json个数组字段

Filter out specific json array fields of elements using jq

json

aws-cli

jq

JqPlay Demo